MS 375TR Equivalent & Substitute Parts

Part Overview

The MS 375TR is a 375 mA board mount axial fuse rated for 125 V AC/DC operation, manufactured by Bel Fuse Inc. This component is classified as obsolete, making equivalent substitutes necessary for ongoing production and maintenance applications. The fuse provides slow blow response characteristics with a breaking capacity of 50A AC and 300A DC, suitable for circuit protection in industrial and commercial electronics.

Substiute Parts

MS 375TR

Bel Fuse Inc.In Stock: 838MS 375TR Datasheet

Current PartRFQ

0473.375MRT1L

Littelfuse Inc.In Stock: 154950473.375MRT1L Datasheet

DirectRFQ

0473.375YRT1L

Littelfuse Inc.In Stock: 12050473.375YRT1L Datasheet

DirectRFQ

0251.375MXL

Littelfuse Inc.In Stock: 18530251.375MXL Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the MS 375TR is determined by matching the following critical electrical and mechanical parameters:

• Current Rating: 375 mA (exact match required)
• Voltage Rating: 125 V AC and 125 V DC (exact match required)
• Mounting Type: Through Hole (exact match required)
• Fuse Type: Board Mount, Axial configuration (exact match required)
• Operating Temperature Range: -55°C ~ 125°C (exact match required)

Substitute parts are grouped into two categories:

Direct Substitutes (PICO® II 473 Series): Parts 0473.375MRT1L and 0473.375YRT1L are functionally equivalent with identical electrical ratings and response characteristics. These differ only in packaging format (Cut Tape vs. Tape & Reel) and are interchangeable at the component level.

Similar Substitute (PICO® II 251 Series): Part 0251.375MXL matches all critical electrical and mechanical parameters but employs fast blow response instead of slow blow. This part is suitable only for applications where fast blow response is acceptable or preferred.

Parameter Comparison

Engineering Selection Recommendations

For applications requiring direct replacement of the MS 375TR with identical slow blow response characteristics, select either 0473.375MRT1L or 0473.375YRT1L from the Littelfuse PICO® II 473 series. Both parts are active products with current manufacturing support and ROHS3 compliance, ensuring long-term availability and regulatory alignment.

The choice between 0473.375MRT1L (Cut Tape packaging) and 0473.375YRT1L (Tape & Reel packaging) depends on procurement and assembly requirements. Tape & Reel packaging is standard for automated assembly processes, while Cut Tape is suitable for manual or low-volume applications.

The 0251.375MXL substitute from the PICO® II 251 series is applicable only when fast blow response is functionally acceptable. This part maintains identical current and voltage ratings with equivalent breaking capacity and temperature range, but the response time difference must be validated against circuit protection requirements before selection.

All substitute parts carry CSA or cURus approvals, maintaining compliance with the original MS 375TR certification profile.

Frequently Asked Questions (FAQ)

Q: Can 0473.375MRT1L and 0473.375YRT1L be used interchangeably with the MS 375TR?

A: Yes. Both parts are electrically and mechanically identical to the MS 375TR, differing only in packaging format. They provide the same 375 mA current rating, 125 V AC/DC voltage rating, slow blow response, and operating temperature range. Selection between them depends on procurement format requirements.

Q: What is the difference between the PICO® II 473 and PICO® II 251 series substitutes?

A: The primary difference is response time. The 473 series (0473.375MRT1L, 0473.375YRT1L) maintains the slow blow characteristic of the original MS 375TR. The 251 series (0251.375MXL) employs fast blow response. Fast blow fuses interrupt circuits more rapidly, suitable for protecting sensitive components. Slow blow fuses tolerate temporary current surges, suitable for inductive loads. Application requirements determine which is appropriate.

Q: Are there physical dimension differences between these substitutes?

A: Yes. The MS 375TR measures 0.125" diameter × 0.280" length. The PICO® II 473 series measures 0.135" diameter × 0.280" length. The PICO® II 251 series measures 0.110" diameter × 0.280" length. These dimensional variations may affect board layout and mechanical fit. Verify PCB hole spacing and component clearances before final selection.

Q: What packaging options are available for the substitute parts?

A: The 0473.375MRT1L is supplied in Cut Tape (CT) packaging with 15,400 pieces in stock. The 0473.375YRT1L is supplied in Tape & Reel (TR) packaging with 1,120 pieces in stock. The 0251.375MXL is supplied in Bulk packaging with 1,776 pieces in stock. Packaging selection aligns with assembly process requirements and order quantities.

Q: Do all substitute parts meet the same regulatory approvals as the MS 375TR?

A: The MS 375TR carries CE, CSA, and cURus approvals. The PICO® II 473 series carries CSA and UR approvals. The PICO® II 251 series carries CSA and cURus approvals. Verify that the selected substitute meets all regulatory requirements for your specific application and market.

Q: What is the DC cold resistance difference between the MS 375TR and its substitutes?

A: The MS 375TR has 1.66 Ohms DC cold resistance. The PICO® II 473 series has 1.74 Ohms. The PICO® II 251 series has 0.395 Ohms. These variations may affect circuit behavior during normal operation. Applications sensitive to fuse resistance should account for these differences in circuit analysis.